DEBIAN-CVE-2026-39984
Sigstore Timestamp Authority is a service for issuing RFC 3161 timestamps. Versions 2.0.5 and below contain an authorization bypass vulnerability in the VerifyTimestampResponse function. VerifyTimestampResponse correctly verifies the certificate chain signature, but the TSA-specific constraint checks in VerifyLeafCert uses the first non-CA certificate from the PKCS#7 certificate bag instead of the leaf certificate from the verified chain. An attacker can exploit this by prepending a forged certificate to the certificate bag while the message is signed with an authorized key, causing the library to validate the signature against one certificate but perform authorization checks against another. This vulnerability only affects users of the timestamp-authority/v2/pkg/verification package and does not affect the timestamp-authority service itself or sigstore-go. The issue has been fixed in version 2.0.6.
DEBIAN-CVE-2026-39984
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-39984
golang-github-sigstore-timestamp-authority
Source reference: /affected/0/package/name
- Affected versions
- 1.2.3-2
Source reference:
/affected/0/versions1.2.9-1Source reference:
/affected/0/versions2.0.3-1Source reference:
/affected/0/versions2.0.3-2Source reference:
/affected/0/versions2.0.4-1Source reference:
/affected/0/versions2.1.0-1Source reference:
/affected/0/versions2.1.2-1Source reference:
/affected/0/versions2.1.3-1Source reference:
/affected/0/versions2.1.3-2Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
golang-github-sigstore-timestamp-authority
Source reference: /affected/1/package/name
- Affected versions
- 1.2.3-2
Source reference:
/affected/1/versions1.2.9-1Source reference:
/affected/1/versions2.0.3-1Source reference:
/affected/1/versions2.0.3-2Source reference:
/affected/1/versions2.0.4-1Source reference:
/affected/1/versions - Fixed versions
- 2.1.0-1
Source reference:
/affected/1/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "golang-github-sigstore-timestamp-authority",
"purl": "pkg:deb/debian/golang-github-sigstore-timestamp-authority?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1.2.3-2",
"1.2.9-1",
"2.0.3-1",
"2.0.3-2",
"2.0.4-1",
"2.1.0-1",
"2.1.2-1",
"2.1.3-1",
"2.1.3-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39984.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.1.0-1"
}
]
}
],
"package": {
"name": "golang-github-sigstore-timestamp-authority",
"purl": "pkg:deb/debian/golang-github-sigstore-timestamp-authority?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1.2.3-2",
"1.2.9-1",
"2.0.3-1",
"2.0.3-2",
"2.0.4-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39984.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #57655 · Revision 1
- Added to Heist Feed
- Publisher date